Cypress Semiconductor Corp CY7C1512V18-250BZC

Overview

CY7C1512V18 from Cypress Semiconductor is a 4M × 18-bit (72-Mbit), 1.8V QDR-II SRAM with separate read/write ports, 250 MHz clock operation, DDR interfaces on both ports (500 MHz data rate), and 165-ball FBGA (15 × 17 × 1.4 mm) packaging. It delivers concurrent high-bandwidth memory access for network packet buffering in telecom line cards.

For engineers reviewing the CY7C1512V18 datasheet, CY7C1512V18 pinout, CY7C1512V18 application, or CY7C1512V18 equivalent, key selection criteria include burst depth (2-word), dual-clock timing (K/K and C/C), echo clocks (CQ/CQ), HSTL I/O compliance, and synchronous self-timed write capability.

Technical Context

The CY7C1512V18 implements QDR-II architecture with fully independent read and write ports sharing a multiplexed 21-bit address bus. Each port uses dedicated DDR interfaces: write data sampled on rising edges of K/K, read data driven on rising edges of C/C, with echo clocks CQ/CQ synchronized to output clocks for precise capture.

It features on-chip Delay Lock Loop (DLL) for accurate data placement, JTAG 1149.1 test access, variable-drive HSTL output buffers, and synchronous self-timed writes. Core VDD = 1.8 V ±0.1 V; I/O VDDQ = 1.4–1.8 V; supports depth expansion via RPS/WPS and byte write selects BWS[1:0].

Key Specifications

Pinout & Package

Package: 165-ball Fine-Pitch Ball Grid Array (FBGA), 15 mm × 17 mm × 1.4 mm body, 0.8 mm ball pitch, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-bandwidth dual-port SRAM applications.

Compared with AS7C3256B-25JCIN and IS61WV102418BLL-10BLI, the CY7C1512V18 uniquely delivers 72 Mbit density with true concurrent read/write, DDR timing, and echo-clocked outputs-making it irreplaceable for 250 MHz fabric-attached buffering where deterministic latency and zero bus turnaround are mandatory.

Availability

CY7C1512V18 is available at Aetrix Electronics and suitable for network packet buffering, switch fabric interface, telecom line card buffering, and high-speed test equipment memory requiring stable component supply and long-term obsolescence management.

Supply support for CY7C1512V18 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Cypress Semiconductor (now part of Infineon Technologies) designs high-performance memory and programmable solutions for communications, industrial, and automotive markets.

The QDR-II SRAM product line targets high-speed networking and datacom applications requiring deterministic latency, concurrent access, and DDR bandwidth-specifically engineered for switch fabric, packet buffer, and traffic manager subsystems.

FAQ

What is the function of the ZQ pin on CY7C1512V18?

The ZQ pin calibrates the output driver impedance of Q[17:0] and CQ/CQ signals. It must be connected to a precision resistor (typically 100 Ω) tied to ground; alternatively, connecting ZQ directly to VDDQ enables minimum output impedance mode. Leaving ZQ unconnected or tying it to GND violates specification and risks signal integrity failure.

Can CY7C1512V18 operate in single-clock mode?

Yes-CY7C1512V18 supports single-clock mode where K and C are tied together (and K and C likewise). In this configuration, data is latched and driven using only the K/K pair, eliminating need for separate output clocks. However, echo clock generation shifts to K/K, and timing margins differ from dual-clock operation per datasheet Table 10.

How does the BWS[1:0] signal control write operations?

BWS[1:0] are active-low byte write selects that enable partial 9-bit writes to the 18-bit D[17:0] bus. BWS0 controls D[8:0], BWS1 controls D[17:9]. When either is deasserted, its corresponding 9-bit segment is ignored during the write cycle, preserving existing data in those bits-enabling efficient 9-bit metadata updates without full-word read-modify-write.

Is the DOFF pin required to be pulled high in normal operation?

Yes-DOFF must be held HIGH (tied to VDDQ) for normal DLL-enabled operation. Pulling DOFF LOW disables the internal Delay Lock Loop, causing output timing to deviate significantly from datasheet specifications (e.g., increased CQ-to-Q skew, reduced setup/hold margins). Use DOFF=LOW only during characterization with revised timing analysis.